Amazon Fresh (https://fresh.amazon.com) is in Northern CA, but I don't think they service the south bay yet.
They do as of today!
Safeway delivers. Pretty sure it's not free, but not sure if they have a delivery fee or a minimum order.
Safeway usually has deals like "buy x of these items for free delivery", so I never paid for delivery using them. They're pretty good, but not same day.